YourYour video is too dark to see on the second half try to re record it with better quality
A much easier method is just to use photo mode. Go to the wire gate you can see through and see the red chest. Then face away from gate. Now go to photo mode camera will be facing gate. Maneuver up wall and onto roof of room and then go down to the chest. Now while right next to chest hit your B button and then quickly your X button to open the chest. There’s several places in game this works for various chests.
Props my man. This is indeed the easiest way to get the chest open. That other way, with all the jumping and clipping through the map is much too complicated and I can barely see where he’s going cuz it’s too dark.